@@ -546,4 +546,7 @@ int inet6_fill_ifmcaddr(struct sk_buff *skb,
const struct ifmcaddr6 *ifmca,
struct inet6_fill_args *args);
+int inet6_fill_ifacaddr(struct sk_buff *skb,
+ const struct ifacaddr6 *ifaca,
+ struct inet6_fill_args *args);
#endif
@@ -100,7 +100,11 @@ enum {
RTM_GETMULTICAST,
#define RTM_GETMULTICAST RTM_GETMULTICAST
- RTM_GETANYCAST = 62,
+ RTM_NEWANYCAST = 60,
+#define RTM_NEWANYCAST RTM_NEWANYCAST
+ RTM_DELANYCAST,
+#define RTM_DELANYCAST RTM_DELANYCAST
+ RTM_GETANYCAST,
#define RTM_GETANYCAST RTM_GETANYCAST
RTM_NEWNEIGHTBL = 64,
@@ -782,6 +786,8 @@ enum rtnetlink_groups {
#define RTNLGRP_IPV4_MCADDR RTNLGRP_IPV4_MCADDR
RTNLGRP_IPV6_MCADDR,
#define RTNLGRP_IPV6_MCADDR RTNLGRP_IPV6_MCADDR
+ RTNLGRP_IPV6_ACADDR,
+#define RTNLGRP_IPV6_ACADDR RTNLGRP_IPV6_ACADDR
__RTNLGRP_MAX
};
#define RTNLGRP_MAX (__RTNLGRP_MAX - 1)
@@ -5241,9 +5241,9 @@ int inet6_fill_ifmcaddr(struct sk_buff *skb,
}
EXPORT_SYMBOL(inet6_fill_ifmcaddr);
-static int inet6_fill_ifacaddr(struct sk_buff *skb,
- const struct ifacaddr6 *ifaca,
- struct inet6_fill_args *args)
+int inet6_fill_ifacaddr(struct sk_buff *skb,
+ const struct ifacaddr6 *ifaca,
+ struct inet6_fill_args *args)
{
struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
int ifindex = dev ? dev->ifindex : 1;
@@ -278,6 +278,40 @@ static struct ifacaddr6 *aca_alloc(struct fib6_info *f6i,
return aca;
}
+static void inet6_ifacaddr_notify(struct net_device *dev,
+ const struct ifacaddr6 *ifaca, int event)
+{
+ struct inet6_fill_args fillargs = {
+ .portid = 0,
+ .seq = 0,
+ .event = event,
+ .flags = 0,
+ .netnsid = -1,
+ };
+ struct net *net = dev_net(dev);
+ struct sk_buff *skb;
+ int err = -ENOMEM;
+
+ skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) +
+ nla_total_size(sizeof(struct in6_addr)) +
+ nla_total_size(sizeof(struct ifa_cacheinfo)),
+ GFP_KERNEL);
+ if (!skb)
+ goto error;
+
+ err = inet6_fill_ifacaddr(skb, ifaca, &fillargs);
+ if (err < 0) {
+ WARN_ON_ONCE(err == -EMSGSIZE);
+ nlmsg_free(skb);
+ goto error;
+ }
+
+ rtnl_notify(skb, net, 0, RTNLGRP_IPV6_ACADDR, NULL, GFP_KERNEL);
+ return;
+error:
+ rtnl_set_sk_err(net, RTNLGRP_IPV6_ACADDR, err);
+}
+
/*
* device anycast group inc (add if not found)
*/
@@ -333,6 +367,8 @@ int __ipv6_dev_ac_inc(struct inet6_dev *idev, const struct in6_addr *addr)
addrconf_join_solict(idev->dev, &aca->aca_addr);
+ inet6_ifacaddr_notify(idev->dev, aca, RTM_NEWANYCAST);
+
aca_put(aca);
return 0;
out:
@@ -375,6 +411,8 @@ int __ipv6_dev_ac_dec(struct inet6_dev *idev, const struct in6_addr *addr)
ip6_del_rt(dev_net(idev->dev), aca->aca_rt, false);
+ inet6_ifacaddr_notify(idev->dev, aca, RTM_DELANYCAST);
+
aca_put(aca);
return 0;
}
This change introduces a mechanism for notifying userspace applications about changes to IPv6 anycast addresses via netlink. It includes: * Addition and deletion of IPv6 anycast addresses are reported using RTM_NEWANYCAST and RTM_DELANYCAST. * A new netlink group (RTNLGRP_IPV6_ACADDR) for subscribing to these notifications. This enables user space applications(e.g. ip monitor) to efficiently track anycast addresses through netlink messages, improving metrics collection and system monitoring. It also unlocks the potential for advanced anycast management in user space, such as hardware offload control and fine grained network control. Cc: Maciej Żenczykowski <maze@google.com> Cc: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Yuyang Huang <yuyanghuang@google.com> --- include/net/addrconf.h | 3 +++ include/uapi/linux/rtnetlink.h | 8 ++++++- net/ipv6/addrconf.c | 6 +++--- net/ipv6/anycast.c | 38 ++++++++++++++++++++++++++++++++++ 4 files changed, 51 insertions(+), 4 deletions(-)